Living World episodes differ a lot in quality, don't they? Sometimes maps are great but the story content is bad, sometimes the other way round. Sometimes events are fun and sometimes they are not. Sometimes the story knocks you off your feet and sometimes it just makes you want to bang your head against the wall. There is a distinct lack of consistency with LW content, and a full season rarely feels satisfying because its episodes don't go well together in regard of their quality: the writing (i.e., its presentation, dialogue, plot consistency etc.), story length, story missions and their level of challenge and innovation, cinematics, map content and design, as well as achievements.
That's why I believe that Expansions are preferable: you have one team working on one, and as a result the elements all fit together and you get a full-fledged, (mostly) polished product. I don't mind waiting for expansions, the time in between could be filled with frequent Side Story releases (which are always tons of fun to do) instead of LW episodes. (Also, old content could use some polishing-up.)
I would like ANet to reconsider their approach on the type of content they spend their resources on. In my honest opinion, Living World has proven to be a disappointment overall. You impatiently wait for the continuation of the story, don't know what to expect, and often end up feeling let down by the results of what, no doubt, was the fruit of hard labor on the devs' end. The rush in releasing episodes ASAP as well as the inconsistency due to different teams working on them does not seem to be a good utilization of said resources.